Hi Mechfab,
Looking online, experts seem a bit divided on this one. Some will say 6 months until your body develops HBsAG, which is the test to take that tells you if you have a current infection. Others say 3 months. In fact, the CDC say that HBsAG is present 1-9 weeks, with an average of 4.
The CDC link can be found here:
http://www.cdc.gov/ncidod/diseases/hepatitis/b/faqb.htm
I'm in the same boat as you. I've tested negative for HepB (HBsAG) and HepC (antibodies) at 18 weeks. But even though these results are re-assuring to an extent, it's scary when there are other opinions and it's your own health you are concerned about.
By the way, don't beat yourself up about unprotected oral. I'd say that most oral is unprotected. You've got to be pretty unlucky to catch something that way, when you think about how often it happens. My exposure was the same. All we can do is learn from our mistakes and move forward.
Hope that helps,
Pete.
Hbv is a classic Std. 50 days on average, range is up to 180 days.